Chickens Abandoned Coop

Our free rangers have always put themselves to bed in the coop except for one prefers a bush since her rooster had to find a new home. Last night I heard a racket in the coop and ran out to look. 2 hens were in the run area seemingly frightened while the other 2 were firmly on the same roost. Lots of feathers but no other sign of intruder. Tonight they all have picked the bush or porch for resting tonight. Thoughts?